The invention relates to improvements in machines for treating flowable materials, especially viscous materials, and more particularly to improvements in machines for transferring metered quantities of flowable material (such as yoghurt) from a source (e.g., a large vessel) into a succession of smaller receptacles (such as cups or jars).
Presently known machines of the above outlined character comprise a housing with a rotary metering device therein. The internal chamber of the metering device receives a metered quantity of flowable material in a first angular position and discharges the metered quantity in a second angular position with reference to the housing. Such machines operate quite satisfactorily for the admission of metered quantities of cream, yoghurt, other types of milk products and other raw or cooked or otherwise processed foodstuffs of many kinds. The means for indexing the metering device includes a piston rod which has a polygonal outline and is reciprocable in a bearing in the interior of the metering device. The piston rod further serves as a means for reciprocating a piston which is movable in the chamber of the metering device to draw flowable material into the chamber in the first position and to expel flowable material from the chamber in the second position of the metering device. It has been found that the piston rod, which performs the plural functions of reciprocating the piston and of transmitting torque to the metering device, undergoes extensive wear when the machine is in use.